In such airbag modules, various limiting conditions must be taken into account for the development of the connection between the generator carrier and the covering cap. Firstly, it must be ensured that the connection withstands all forces occurring during the sudden unfolding of the gas bag, because a release of parts of the cap or of the cap as a whole, which tears open and folds out along given lines on activation of the gas bag, caused by an accident, must be avoided under all circumstances with regard to the risk of injury related therewith. The development of the connection is made difficult in that these forces are effective not only in the direction of unfolding of the air bag, but momentarily also in the opposite direction.
In addition, it is to be noted that the cap of an airbag module generally is designed as an actuating member for the vehicle horn and for this is arranged so as to be movable against a return force approximately parallel to the steering wheel axis across at least the contact distance relative to the steering wheel. With the connection between the cap and generator carrier, care must be taken that these parts are secured to each other so as to be immovable relative to each other, so that the horn function or the contact distance to be set in close limits can be maintained.
Finally, the connection between the covering cap and the generator carrier should be as simple as possible and preferably be made without any tools.
Conventional connections between the cap and the generator carrier do not always fulfill the above-mentioned requirements optimally, so that engineers are constantly endeavoring to further improve these connections. In addition to this is the fact that motor vehicle steering wheels are likewise constantly further developed, which can lead to conventional fastening methods no longer being able to be applied and therefore likewise having to be modified.